The present invention relates to dock restraint systems used to secure vehicles, such as semitrailers, proximate a loading dock. More specifically, the present invention relates to a status indicator and hook control system and hook assembly used with dock restraint systems.
Vehicle restraint systems are commonly used to secure a vehicle, such as a semitrailer relative to a loading dock. When engaged, such restraint systems prevent translation of the vehicle relative to the loading dock and/or a dock plate. As commonly understood by those skilled in the art, a dock plate is a ramp or the like that provides a transition from dock areas to the load space associated with the vehicle. Preferably, the vehicle is secured such that the bed of the vehicle's storage area can be conveniently accessed by personnel and/or equipment associated with loading and unloading operations while the position of the vehicle is maintained relative to the dock or dock area. This allows the contents of the storage area to be quickly and efficiently exchanged between the facility and over the road transport vehicles without fear of the formation of a gap between the dock and the vehicle and/or the load area or bed of the transport vehicle. U.S. Pat. No. 6,190,109, which is incorporated herein by reference, discloses one such dock plate or leveler and a dock restraint system associated therewith.
In many dock restraint systems, the vehicle restraint device or system includes a carriage that is adjustably mounted to a mounting plate connected to a wall adjacent to the dock. The carriage is commonly configured to slideably cooperate with the underside of an underride or rear impact guard that is associated with the frame of the load vehicle. Commonly, the restraining member is pivotably supported by the carriage such that the restraint can be selectively engaged and disengaged from interaction with the rear impact guard. User interaction with the restraint assembly is commonly effectuated via a control panel. The control panel is commonly configured to receive input signals from loading personnel to effectuate a desired “secure” or “release” operation of the associated restraint relative to an underlying vehicle. The control system is further commonly configured to provide a restraint status indicator to the vehicle operator as well as surrounding personal to provide an indication that the restraint has achieved a desired orientation relative to the underlying vehicle to achieve the desired “secure” or “released”, or “engaged or “disengaged” status of the restraint relative to the underlying vehicle.
Translation of the vehicle during loading and unloading operations can result in “jamming” of the restraining member and/or undesired interference of the restraining member with the vehicle guard. This undesired interference or “jamming” of the restraint system with the underlying vehicle can result in the inability to engage or disengage the restraining member from interaction with the vehicle guard when desired. Generally, the inability to achieve the desired engagement or disengagement of the restraining member or dock hook from the vehicle must be resolved by physically moving the vehicle relative to the carriage and/or restraint to effectuate the desired engagement and/or disengagement of the restraining member from the vehicle or trailer associated with the loading dock. Such undesired interaction proves problematic when trailers are left in a loading dock without an associated power vehicle such as a tug, tractor, or semi-tractor or operators or drivers are unavailable to operate the vehicle being loaded.
Commonly, the control system associated with operation of the underlying restraint system includes a plurality of discrete indicators that designate the respective status of the underlying restraint system. One common methodology includes providing a plurality of light elements, commonly of different colors and/or positioned at different locations, that designate the discrete condition of the underlying restraint system as being one or more of engaged and secure, engaged but non-secure, disengaged, and/or disengaged and fully retracted. The various locations and/or different color indications or designations associated with the various discrete conditions associated with operation of the underlying restraint system can leave personnel and/or vehicle operators unclear or confused as to a current condition associated with a discrete vehicle restraint system. Such confusion or misinterpretation can be exacerbated by the various different presentation methodologies associated with assessing the status of the discrete vehicle restraint systems when discrete facilities are equipped with restraint status, indicia, or indicator systems.
Accordingly, there is a need for a vehicle restraint system which can be selectively engaged and disengaged from discrete vehicles having various vehicle frame configurations and which provides a more readily discernable restraint condition or status indicia.